1. Field of the Invention
The present invention relates to a backlight module and a lamp holder thereof, and particularly to a direct-type backlight module and a lamp holder thereof for convenience on assembly of lamps spaced at different intervals.
2. Description of Prior Art
In recent years, LCDs (Liquid Crystal Displays) gradually replaces the conventional CRT (Cathode-Ray Tube) displays to be a mainstream product in the display market because of its high compactness, high luminance, lower-power consumption and radiation-free advantages.
However, since the liquid crystal molecules spread in an LCD display panel have not a luminance property, a backlight module is utilized to serve as a plane light source that is essential for the display panel to realize image display. Thus, the backlight module has become an indispensable key component in the LCD device.
In general, the backlight modules may be classified into an edge type and a direct type according to different position where the lamp is disposed in the module. The edge-type backlight module allocates a lamp on the lateral side of the display panel and therefore is suitable for an thin-shaped display panel with a small size. In contrast, the direct-type backlight module allocates multiple lamps on a bottom of the display panel, and therefore is suitable for a large-size display panel. The direct-type backlight module generally includes a base plate, a plurality of lamps fixedly arranged on the base plate, and a diffusion plate located above both the base plate and the lamps and thereby outwardly diffusing the lights emitted from the lamps along a vertical direction with regard to the diffusion plate so as to provide the LCD display panel with a plane light source.
Nevertheless, to firmly retain the lamps on the base plate, a lamp holder is often needed for the direct-type backlight module. As shown in FIG. 1, a conventional lamp holder 7 includes a base portion 71 is fixed over a base plate 8 and a plurality pair of clips 72 upwardly projecting from the base portion 71. Each pair of clips 72 is spaced at a predetermined interval to contribute a resilient strength to grip of a corresponding lamp 9. The clips 72 and the base portion 71 are integrally formed by injection molding. However, there often causes some problems in application of the above conventional lamp holder. For example, although this integrally-formed lamp holder can simultaneously retain a plurality of lamps, it only can retain a plurality of lamps spaced in a predetermined or fixed interval for a specific LCD type. For other LCD types having different-interval spaced lamps, it is not applicable since the fixed distance between adjacent pairs of clips of this integrally-formed lamp holder is not adjustable arbitrarily. In this case, it would be unavoidable to redesign a new type lamp holder for suiting the other type LCD type, which requires new mold development. Consequentially, this would causes increase of development time and cost.
In addition, if there are manufacture tolerances appearing in the integrally-formed lamp holder to cause the intervals between each adjacent pairs of clips inconsistent that is not adjustable individually, the pairs of clips of this integrally-formed lamp holder can not precisely grip all corresponding lamps.
As described above, the conventional lamp holder is rather inconvenient in assembly. Hence, an improved direct-type backlight module and a lamp holder thereof adequate for assembly of different-intervals spaced lamps are desired.